1. Field of the Invention
This invention is directed to degassing devices for liquid steel. More specifically the invention is directed to degassing by vacuum in a casting ladle sealed by a lid. In this it should be noted that apart from the vacuum-sealed lid the discharge nozzle for pouring the steel at the floor of the casting ladle should also be sealed vacuum-tight. This is especially important for processes in which the steel to be treated runs into the casting ladle under vacuum and the steel running in is to be subjected to the effect of the vacuum from the beginning. Whether it is a stopper control or a sliding nozzle, a discharge nozzle which is not completely sealed means a leak which prevents the deep vacuum desired initially and during treatment.
2. Discussion of the Prior Art
It has been suggested that the casting ladle is sealed vacuum-tight in a stopper rod control or in a slide nozzle by metal hoods arranged under the ladle base completely covering the discharge nozzle. These metal hoods, which have to be constructed detachably especially in a sliding nozzle, mean an expensive construction and are hard to manipulate. The invention has therefore set the object of developing a vacuum sealing which is easily manipulated and cheaply produced.